1979 l48 battery drain issues
Thread Starter
Cruising
Joined: May 2015
Posts: 11
Likes: 1
1979 l48 battery drain issues
i have a 1979 l48 that starts up fine and runs good. sorry for a lot of info just want all the help i can get.
only thing is that everywhere I go if im going to let the car sit for a while i disconnect the positive cable on the battery so that it doesnt drain. when i connect the battery back sometimes if its too tight the battery doesnt connect so i loosen it and its good everything turns on and car turns over usually second try.
ive gone through two new batteries both times the car sits and battery is connected but after just a day the car battery was dead and nothing would turn on. ive left the car to a corvette mechanic that was confident everything was fine and working and that there shouldnt be a battery drain issue since he had it connected the 3 days it was there. also the GEN is always on and im not sure why exactly could this have to do with battery?
only thing is that everywhere I go if im going to let the car sit for a while i disconnect the positive cable on the battery so that it doesnt drain. when i connect the battery back sometimes if its too tight the battery doesnt connect so i loosen it and its good everything turns on and car turns over usually second try.
ive gone through two new batteries both times the car sits and battery is connected but after just a day the car battery was dead and nothing would turn on. ive left the car to a corvette mechanic that was confident everything was fine and working and that there shouldnt be a battery drain issue since he had it connected the 3 days it was there. also the GEN is always on and im not sure why exactly could this have to do with battery?
Melting Slicks
Joined: Jul 2009
Posts: 2,091
Likes: 40
i have a 1979 l48 that starts up fine and runs good. sorry for a lot of info just want all the help i can get.
only thing is that everywhere I go if im going to let the car sit for a while i disconnect the positive cable on the battery so that it doesnt drain. when i connect the battery back sometimes if its too tight the battery doesnt connect so i loosen it and its good everything turns on and car turns over usually second try.
ive gone through two new batteries both times the car sits and battery is connected but after just a day the car battery was dead and nothing would turn on. ive left the car to a corvette mechanic that was confident everything was fine and working and that there shouldnt be a battery drain issue since he had it connected the 3 days it was there. also the GEN is always on and im not sure why exactly could this have to do with battery?
only thing is that everywhere I go if im going to let the car sit for a while i disconnect the positive cable on the battery so that it doesnt drain. when i connect the battery back sometimes if its too tight the battery doesnt connect so i loosen it and its good everything turns on and car turns over usually second try.
ive gone through two new batteries both times the car sits and battery is connected but after just a day the car battery was dead and nothing would turn on. ive left the car to a corvette mechanic that was confident everything was fine and working and that there shouldnt be a battery drain issue since he had it connected the 3 days it was there. also the GEN is always on and im not sure why exactly could this have to do with battery?
So ...you ve shorts in components or wires fried together , lamp shorts, there are a hundred items , it's near impossible not being their with the car and teaching at the same time
If you aren't good with electric circuits and trouble shooting , you may want to take it to shop and get it straightened out . They have the years of trouble shooting skills to trace the circuits and pin point the problems.
Could be compounded by several issues at once .
Intermediate
Joined: Aug 2013
Posts: 39
Likes: 1
From: Greenville South Carolina
I agree with LS4 Pilot. I also own a 79 and it had electrical issues and it took some time to locate the shorts. Every older vehicle I have ever owned developed electrical issues due to normal operations, dirt, water, salt, and other things that promote corrosion. When you love cars like most of us do...it is just part being a car guy. I highly recommend getting with someone that can teach you how to perform a voltage drop test and explain a systematic approach to finding the cause of the electrical issue(s). Finally, one member gave me some advice that has kept me sane while troubleshooting and that is hooking up a battery tender every time I get home (cheap insurance from Wally world). Good luck. HRP
Le Mans Master
Joined: Jan 2001
Posts: 9,249
Likes: 221
From: Dryden MI
Get your alternator checked for a short, make sure your glove box lite and hood lite are off, interior liters too, that they turn off. Sounds like a big drain on battery, that is why I suggest the alternator first, most rebuild shops will test it for you.
Burning Brakes
Joined: Oct 2013
Posts: 992
Likes: 28
From: Sutton MA
The GEN light only comes on when the ignition is turned to start the car. So that would concern me. Now I'll just throw this in here. because I chased a battery drain in our 79 and what really solved the problem was at the starter for me. Just check to see if there is a little black wire with a big round end on it, it should be connected to the block or transmission and block as a ground. I found ours on the positive post of the starter. which is a common mistake because the connector is the same size as the positive cable that connects to the starter.
That would drain our battery dead in two days sometimes only a day.
That would drain our battery dead in two days sometimes only a day.
Burning Brakes
Joined: Aug 2003
Posts: 1,060
Likes: 19
From: Ocean Springs, MS
St. Jude Donor '07
Had a similar experience with my '81 and it turned out to be a short in the alternator. I have not had any battery draining issues since. BTW, the charging system passed tests with flying colors but the alternator would drain the battery with the ignition off. Good luck.
